Update git submodules

* Update docs/submodules/bottlenecks from branch 'stable/euphrates'
  - roll back the bug-fix for source method

    JIRA: BOTTLENECK-222

    It seems the issue related to environments.
    Just roll back for further actions.

    Change-Id: I9578fb0c2a3aed2fe5b1c704c6baea2e56ca39a9
    Signed-off-by: Yang Yu <Gabriel.yuyang@huawei.com>
    (cherry picked from commit 952db3aa4d1fe889c524d1d70bde0479e638f53e)

diff --git a/docs/submodules/bottlenecks b/docs/submodules/bottlenecks
index 5056e9d..b155081 160000 (submodule)
--- a/docs/submodules/bottlenecks
+++ b/docs/submodules/bottlenecks
@@ -1 +1 @@
-Subproject commit 5056e9d46bffebc98bef05eb12e05f25f5f7811e
+Subproject commit b1550810eb2ed1203efb55ecdbc8dd7865274340